Month: June 2021

These common heterocyclic compound, 41110-29-6, name is Methyl 3-methylpyrazine-2-carboxylate, its traditional synthetic route has been very mature, but the traditional synthetic route has various shortcomings, such as complicated route, low yield, poor purity, etc, below Introduce a new synthetic route. Product Details of 41110-29-6

A solution of mixture of 2-(methoxycarbonyl)-3-methylpyrazine 1-oxide compound with 3-(methoxycarbonyl)-2-methylpyrazine 1-oxide (1:1) (5.1 g, 15.17 mmol) in toluene (50 mL) was cooled to 0 C. To the mixture was added phosphorus oxychloride (2.78 ml, 30.3 mmol) under nitrogen followed by n,n?-dimethylformamide (0.117 ml, 1.517 mmol). The reaction mixture was stirred at room temperature for 4 h and then was heated to 65 C. for 18 h. The mixture was cooled to room temperature, diluted with EtOAc and washed with saturated NaHCO3 solution. The aqueous layer was back-extracted with EtOAc. The combined organic extracts were dried (MgSO4), filtered and concentrated in vacuo. The mixture was purified with ISCO (0% to 50% EtOAc/Hexanes) to afford both isomers: methyl 5-chloro-3-methylpyrazine-2-carboxylate (0.68 g, 48.1% yield) and methyl 6-chloro-3-methylpyrazine-2-carboxylate (1.5 g, 106% yield).

The synthetic route of Methyl 3-methylpyrazine-2-carboxylate has been constantly updated, and we look forward to future research findings.

Reference:
Patent; WHITE, Ryan; ALLEN, Jennifer R.; EPSTEIN, Oleg; HONG, Fang-Tsao; HUA, Zihao; HUMAN, Jason Brooks; LOPEZ, Patricia; OLIVIERI, Philip R.; ROMERO, Karina; SCHENKEL, Laurie; STELLWAGEN, John; TAMAYO, Nuria A.; ZHENG, Xiao Mei; US2014/213581; (2014); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Synthetic Route of 41270-66-0, As we all know, there are many different methods for the synthesis of a compound, and people can choose the synthesis method that suits their own laboratory according to the actual situation. 41270-66-0 name is 5-Chloro-2,3-diphenylpyrazine, This compound is widely used in many fields, so it is necessary to find a new synthetic route. The downstream synthesis method of this compound is introduced below.

[123] Step 1. 2-(1.1.2.2.3.3.4.4-dg-4-((5.6-Diphenylpyrazin-2-yl)(propan-2-yl)amino)butan- l-ol (12b). To a solution of commercially available 5-chloro-2,3-diphenylpyrazine (10) (0.57 g, 2.14 mmol) in NMP (2.0 mL), was added d7-aminoalcohol lib (0.75 g, 5.35 mmol, 2.5 equiv, prepared as described in Example 10). The reaction vessel was sealed and heated to 190 0C for 15 hours, then cooled to ambient temperature. The mixture was diluted with ice water and extracted with Et2O (3 x 20 mL). The combined organic layers were washed successively with water and brine. The resulting organic layer was dried (MgSO4), filtered and concentrated in vacuo. The resulting residue was purified by column chromatography (SiO2, 30-50% EtO Ac/heptane) to afford 12b (0.20 g, 25%). MS (M+H): 370.0

At the same time, in my other blogs, there are other synthetic methods of this type of compound, 5-Chloro-2,3-diphenylpyrazine, and friends who are interested can also refer to it.

Reference:
Patent; CONCERT PHARMACEUTICALS, INC.; HARBESON, Scott L.; MASSE, Craig E.; LIU, Julie F.; WO2011/17612; (2011); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

In the next few decades, the world population will flourish. As the population grows rapidly and people all over the world use more and more resources, all industries must consider their environmental impact. 33332-25-1, name is Methyl 5-chloropyrazine-2-carboxylate belongs to pyrazines compound, it is a common compound, a new synthetic route is introduced below. name: Methyl 5-chloropyrazine-2-carboxylate

a) Methyl 5 -(3,3 -difluoroazetidin- 1 -yl)pyrazine-2-carboxylateTo a stirred solution of methyl 5-chloropyrazine-2-carboxylate (2.0 g, CAS 33332-25-1) in dioxane (45 ml) were added 3,3-difluoroazetidine hydrochloride (1.9 g, CAS 288315-03-7) andtriethylamine (4.19 ml). The reaction mixture was stirred at 45 C overnight. TLC analysis showed the reaction was complete. The reaction mixture was poured into aq. brine and extracted twice with ethyl acetate. The combined organic phases were dried over Na2SO4 and concencentrated in vacuo. The residue was purified by flash column chromatography (silica gel; eluent: 50% ethyl acetate in heptane) to afford methyl 5-(3,3-difluoroazetidin-1-yl)pyrazine-2-carboxylate (1.21 g, 46%) as a white solid. MS (ISP): 230.2 ([M+H]j.

The synthetic route of 33332-25-1 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; F. HOFFMANN-LA ROCHE AG; HOFFMANN-LA ROCHE INC.; GALLEY, Guido; NORCROSS, Roger; PFLIEGER, Philippe; WO2014/72257; (2014); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Electric Literature of 3149-28-8, A common heterocyclic compound, 3149-28-8, name is 2-Methoxypyrazine, molecular formula is C5H6N2O, its traditional synthetic route has been very mature, but the traditional synthetic route has various shortcomings, such as complicated route, low yield, poor purity, etc, below Introduce a new synthetic route.

General procedure: Perfluorobutanesulfonyl azides 1a (715 mg, 2.2 mmol) and pyrazine 2a (2.0 mmol) was mixed without solvent at room temperature, this reaction mixture stirred for 8 h at 120 C, TLC analysis showed the reaction was completed. The product 3aa was obtained by flash column chromatography (using petroleum ether/ethyl acetate=2:1 as eluant) as a yellow solid in 34% yield (234 mg).

The synthetic route of 3149-28-8 has been constantly updated, and we look forward to future research findings.

Reference:
Article; Xiong, Wanting; Zhang, Hongfei; Xin, Yong; Zhu, Shizheng; Tetrahedron; vol. 67; 12; (2011); p. 2232 – 2237;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Adding a certain compound to certain chemical reactions, such as: 109838-85-9, name is (R)-2-Isopropyl-3,6-dimethoxy-2,5-dihydropyrazine, belongs to pyrazines compound, can increase the reaction rate and produce products with better performance than those obtained under traditional synthetic methods. Here is a downstream synthesis route of the compound 109838-85-9, Product Details of 109838-85-9

(2R)-(?)-2,5-Dihydro-3,6-dimethoxy-2-isopropylpyrazine (212 g, 1151 mmol) in dry tetrahydrofuran (600 mL) is cooled to ?78° C. Then n-butyllithium (2.5 M in hexanes, 552 mL, 1381 mmol) is added dropwise, keeping the temperature below ?78° C. After 30 min 4-bromo-2-fluorobenzyl bromide (324 g, 1209 mmol) in dry tetrahydrofurane (120 mL) is added dropwise. The reaction mixture is stirred at ?78° C. for 1 h. The mixture is quenched with saturated NH4Cl solution and extracted three times with ethyl acetate. The organic layer is washed with brine, dried over Na2SO4, filtered and evaporated in vacuo. The residue is purified by flash chromatography (heptane/ethyl acetate=80/20). Yield 60percent.

In the field of chemistry, the synthetic routes of compounds are constantly being developed and updated. I will also mention this compound in other articles, (R)-2-Isopropyl-3,6-dimethoxy-2,5-dihydropyrazine, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; Boehringer Ingelheim International GmbH; VINTONYAK, Viktor; GRAUERT, Matthias; GRUNDL, Marc; PAUTSCH, Alexander; (64 pag.)US2016/75704; (2016); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Synthetic Route of 939412-86-9, These common heterocyclic compound, 939412-86-9, name is (3-Chloropyrazin-2-yl)methanamine hydrochloride, its traditional synthetic route has been very mature, but the traditional synthetic route has various shortcomings, such as complicated route, low yield, poor purity, etc, below Introduce a new synthetic route.

Example 3: Synthesis of 3-(4-Fluorophenyl)-imidazo[l,5-a]pyrazine-8-carboxylic acid (3);To a suspension of 2-aminomethyl-3-chloropyrazine hydrochloride (900 mg, 5 mmol) in dichloromethane (25 mL) is added 4-fluorobenzoyl chloride (730 lL, 6.1 mmol) followed by DIPEA (2.0 mL, 11 mmol). After 1 day, the mixture is concentrated and diluted with saturated aqueous ammonium chloride and extracted with EtOAc (3 x 40 mL). The combined organic layers are washed with brine (3 x 25 mL), dried over magnesium sulfate, filtered and concentrated. The residue is passed through a pad of silica gel using dichloromethane-heptane (1: 1) to load the sample and then eluting with dichloromethane to afford N-(3-chloro-pyrazin-2-ylmethyl)-4-fluoro-benzamide as an oil which partially solidified.

The synthetic route of 939412-86-9 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; BOEHRINGER INGELHEIM INTERNATIONAL GMBH; COOK, Brian Nicholas; KUZMICH, Daniel; WO2011/56440; (2011); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Adding a certain compound to certain chemical reactions, such as: 143591-61-1, name is 3-Bromo-8-chloroimidazo[1,2-a]pyrazine, belongs to pyrazines compound, can increase the reaction rate and produce products with better performance than those obtained under traditional synthetic methods. Here is a downstream synthesis route of the compound 143591-61-1, SDS of cas: 143591-61-1

3-Bromo-8-(methylthio)imidazo|”l,2-a”|pyrazine[00241] A solution of NaSMe (385 mg, 5.497 mmol) in DMSO (4 mL) was added to a solution of 3-bromo-8-bromo/chloroimidazo[l,2-a]pyrazine (1.015 g, 4.581 mmol) in DMSO (20 niL) and the resulting mixture was heated at 1000C for 16 hours. After cooling to room temperature, brine was added and the product then extracted into a DCM/isopropanol (9:1) mixture (3 times). The combined organic layers were washed with brine, dried (MgSO4) and purified by flash column chromatography (2:1, 40-60 petrol:EtOAc) to give the title compound (657 mg; 57%). 1H NMR (d6-DMSO): 8.17 (IH, d, J4.8), 7.91 (IH, d, J4.8), 7.84 (IH, s), 2.61 (3H, s).

At the same time, in my other blogs, there are other synthetic methods of this type of compound, 3-Bromo-8-chloroimidazo[1,2-a]pyrazine, and friends who are interested can also refer to it.

Reference:
Patent; BioMarin IGA, Ltd.; WREN, Stephen Paul; WYNNE, Graham Michael; LECCI, Cristina; WILSON, Francis Xavier; PRICE, Paul Damien; MIDDLETON, Penny; WO2010/69684; (2010); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

In the next few decades, the world population will flourish. As the population grows rapidly and people all over the world use more and more resources, all industries must consider their environmental impact. 108-50-9, name is 2,6-Dimethylpyrazine belongs to pyrazines compound, it is a common compound, a new synthetic route is introduced below. Product Details of 108-50-9

First, a synthesis method of an intermediate, 2-chloro-3,5-dimethylpyrazine is described. 7.12 g of 2,6-dimethylpyrazine and 6.5 mL of dimethylformamide (abbreviation : DMF) were put in a three-neck flask equiiped with a drop funnel and a thermometer, and the inside was refluxed under a nitrogen atmosphere. 6.7 mL of sulfuric chloride was put in a drop funnel and the reaction container was soaked in an ice bath. While the reaction solution was being stirred, the sulfuric chloride was dropped in such a way that the temperature of the solution be kept 45 C +/- 5 C. After that, water was added after it was confirmed that the temperature of the solution was 40 0C or lower. After it was confirmed again that the temperature of the solution was 40 0C or lower, an aqueous sodium hydroxide was added and the pH of the solution was adjusted to 7 to 8. This solution was subjected to steam distillation. The obtained solution was subjected to extraction using dichloromethane to separate an organic layer. The organic layer obtained was dried with magnesium sulfate. After the drying, the solution was filtrated. After the solvent of this solution was distilled off, the obtained residue was distilled under reduced pressure, so that an objective intermediate was obtained (clear and colorless liquid, yield of 36 %).

The synthetic route of 108-50-9 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; SEMICONDUCTOR ENERGY LABORATORY CO., LTD.; WO2008/149828; (2008); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Synthetic Route of 21943-17-9,Some common heterocyclic compound, 21943-17-9, name is 5-Bromo-3-chloropyrazin-2(1H)-one, molecular formula is C4H2BrClN2O, traditional synthetic route has been very mature, but the traditional synthetic route has various shortcomings, such as complicated route, low yield, poor purity, etc, below Introduce a new synthetic route.

General procedure: A solution of 56 (1.50 g, 7.16 mmol), the appropriate secondary amine (8.59 mmol, 1.20 equiv) and diisopropylethylamine (1.50 mL, 8.59 mmol) in n-butanol (15 mL)was heated in a microwave reactor using variable wattage to 140 C for 1 h. The mixture was concentrated and purified by flash column chromatography on silica, eluting with 9:1 dichloromethane/methanol, to give gave 58-63.

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 5-Bromo-3-chloropyrazin-2(1H)-one, its application will become more common.

Reference:
Article; Caldwell, John J.; Veillard, Nicolas; Collins, Ian; Tetrahedron; vol. 68; 47; (2012); p. 9713 – 9728,16;; ; Article; Caldwell, John J.; Veillard, Nicolas; Collins, Ian; Tetrahedron; vol. 68; 47; (2012); p. 9713 – 9728;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Adding a certain compound to certain chemical reactions, such as: 622392-04-5, name is 2-Bromo-5-iodopyrazine, belongs to pyrazines compound, can increase the reaction rate and produce products with better performance than those obtained under traditional synthetic methods. Here is a downstream synthesis route of the compound 622392-04-5, Recommanded Product: 2-Bromo-5-iodopyrazine

Preparation 62: Methyl {(2S)-1 -[(2S)-2-{4-[4-(5-bromopyrazin-2-yl)phenyl]-1 H-imidazol-2-yl}pyrrolidin- 1 -yl]-3-methyl-1 -oxobutan-2- l}carbamateMethod A:To a solution of methyl {(2S)-3-methyl-1-oxo-1-[(2S)-2-{4-[4-(4,4,5,5-tetramethyl-1 ,3,2-dioxaborolan-2- yl)phenyl]-1 H-imidazol-2-yl}pyrrolidin-1-yl]butan-2-yl}carbamate obtained from Preparation 61 (33.00 g, 66.53 mmol) and 2-bromo-5-iodopyrazine obtained from Preparation 10 (24.70 g, 86.67 mmol) in 1 ,4- dioxane (600 mL) and water (150 mL), were added potassium phosphate (28.20 g, 133.01 mmol) and tetrakis(triphenylphosphine)palladium (0) (2.30 g, 1.99 mmol). The mixture was sparged with nitrogen for 10 minutes before heating to reflux for 16 hours. After this time, the reaction was allowed to cool to room temperature, the solvent was removed under reduced pressure and the residue was partitioned between ethyl acetate (250 mL) and water (250 mL). The layers were separated and the organic layer was washed with brine (500 mL), dried over magnesium sulphate. The solvent was removed under reduced pressure to give a black gum. The crude product was purified by flash chromatography (heptane : acetone, 20:80) to give the title compound as a foam ( 22.00 g).LCMS (run time = 25 minutes, System K) Rt= 13.19; m/z 527 and 529 [MH+]H NMR (400 MHz, CD3OD+drop of TFA) : delta= 8.99 (s, 1 H), 8.81 (s, 1 H), 8.25 (d, 2H), 7.94 (s, 1 H) 7.86 (d, 2H), 5.27-5.23 (m, 1 H), 4.24 (d, 1 H), 4.13-4.08 (m, 1 H), 3.88 (m, 1 H), 3.65 (s, 3H), 2.62-2.54 (m, 1 H), 2.31- 2.24 (m, 1 H), 2.20-2.14 (m, 2H), 2.09-2.00 (m, 1 H), 0.93 (d, 3H), 0.88 (d, 3H).

In the field of chemistry, the synthetic routes of compounds are constantly being developed and updated. I will also mention this compound in other articles, 2-Bromo-5-iodopyrazine, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; PFIZER LIMITED; MILBANK, Jared Bruce John; TRAN, Thien Duc; WAKENHUT, Florian; WO2011/154871; (2011); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem